ECH (also known as “EPI”) is of particular interest. It is for instance used as a building block in the manufacture of plastics, epoxy resins, phenoxy resins and other polymers. It has been used as a solvent for cellulose, resins and paints and it has found use as an insect fumigant. ECH may react with water, forming the corresponding diol.
Conventional ECH production routes involve the use of chloride containing oxidants, such as HOCl. This method suffers a.o. from a relatively large amount of co-produced chloride salts.
Despite the strong interest in ECH, a high atom-efficient production route without the coproduction of salts and/or other byproducts is not yet available. Moreover, alternative preparation methods suffer from side reactions and/or isolation problems. The ECH typically has to undergo various purification steps before it can be used for subsequent reactions.
For instance, the process for the manufacture of ECH in WO2004/048353 is carried out in a reaction medium comprising at least 75% w of organic material, causing significant isolation problems. Moreover, it is known from this reference and other references wherein ECH is made that the product of such processes frequently comprises both epichlorohydrin and the various byproducts resulting from the opening of the oxirane ring, namely 1-chloro-3-methoxy-2-propanol, 1-chloro-2-methoxy-3-propanol, 3-chloro-1,3-propanediol and 1,3-dichloro-2-propanol.
From the above it is clear the industry is still looking for a commercially feasible process for the manufacture of ECH, in high turnover numbers and at high selectivity, meaning free of byproducts such as diols. This process should also allow the use of an aqueous solvent as reaction medium, to avoid environmental and other problems related to acetonitrile and similar organic solvents. The present invention overcomes these disadvantages.